1. FIELD OF INVENTION
The present invention relates to a camera that can be utilized for three-dimensional (3-D) photography and two-dimensional (2-D) photography.
2. PRIOR ART
In lenticular type three-dimensional (3-D) photography, a plurality of two-dimensional (2-D) views of the scene are taken from a number of horizontally-spaced vantage points and the series of 2-D images is then compressed and printed at the focal plane of each of the lenticules of the lenticular screen to form a 3-D composite image of the field.
In order to take a series of 2-D images at a number of vantage points, one generally takes one of two approaches: 1) using a single-lens camera to take one image at a time at each of the vantage points, or 2) using a multi-lens camera to simultaneously capture a series of 2-D views at one snap. Because the first approach requires special equipment which is usually expensive and bulky, a second approach is more practical for consumer uses.
Multi-lens cameras have been disclosed in a number of U.S. patents which include U.S. Pat. No. 4,800,407 (Lo) where the invention of 3-D cameras with three lenses is disclosed, and U.S. Des. Pat. No. 264,343 (Che) where the invention of 3-D cameras with four lenses is disclosed. Multi-lens cameras are currently available on the market.
The multiple images exposed by a multi-lens camera are a series of regular 2-D images of the same scene photographed at slightly different viewing angles. These regular 2-D images are necessary, as a group, for the composing of a 3-D print but anyone of them can also be used to produce conventional 2-D photographs. Logically, a multi-lens camera should be capable of being utilized as a 3-D camera or as a 2-D camera so that the consumer will not be required to have two cameras, one dedicated to 2-D picture taking and another dedicated to 3-D picture taking. However, all existing consumer 3-D multi-lens cameras adopt a half-frame negative format and this format cannot cover the same field of view normally covered by a full-frame format used in a regular 35mm full-frame camera.
3-D multi-lens cameras are designed to simulate the binocular vision of the human eyes. Therefore, in the design of a consumer 3-D multi-lens camera, the separation between the two endmost lenses must be kept roughly equal to or smaller than the separation distance between the eyes. This lens separation is used in order to assure a good 3-D effect and, at the same time, to avoid excessive parallax which causes a 3-D photograph to become out-of-focus. Since the eye separation distance of the average adult is between 63 and 70mm, the separation between the two endmost lenses in a consumer 3-D multi-lens camera is usually less than or equal to 70mm. This spacing varies depending on the number of lenses on the camera. Furthermore, as all consumer 3-D multi-lens cameras are designed to use a 35mm film, the format for each of the multiple images is about 18mm by 24mm or about half of the regular 35mm full-frame format. Under normal photographic conditions, this relatively narrow format is inadequate for covering the field of view normally covered by a full-frame 2-D camera.
It would be very advantageous for a consumer camera to be capable of exposing multiple images for 3-D photography and also provide a larger image format for 2-D photography. With such a design, the consumer will need only one camera for both 2-D and 3-D picture taking.